You're Lucifers second child and stayed with him. He loves you very much. And you love him too. But sometimes you get into an argument (idk why).

But this time, it ended up worse.

You said something like, "And you wonder why mom left..." He completely lashed out on this. Lilith is a sensitive subject to him because he still loves her. He raises his hand and smacks you straight into the face.

As you cry out in pain, Lucifer realizes what he has done.

Lucifer:"I- I'm sorry! I- "

But before he could finish, you ran into your room

Lucifer:"Duckling, wait! I'm sorry!"

his voice is filled with guilt, and it eats him up inside

Meanwhile, you just take your things and escape through the window. You run away from home.